Purpose: This study aimed to measure diaphragm thickness using ultrasound in adult patients with severe idiopathic scoliosis.
Methods: This prospective case-control study included patients with severe idiopathic scoliosis and a healthy control group. The control and patient groups' demographic features, pulmonary function tests, diaphragm thickness, and thickening fraction measured using ultrasonography were compared.
Results: End-expirium values were similar between the two groups (p = 0.902). However, end of inspirium, change level, and diaphragm thickening fraction were significantly lower in the scoliosis group (p < 0.001 for all). Cobb degree values were inversely correlated with forced expiratory volume in 1 s (%) (r = - 0.909, p < 0.001), forced vital capacity (%) (r = - 0.887, p < 0.001), and end-inspirium thickness (r = - 0.673 and p < 0.001) values. Furthermore, diaphragm thickness at the end of inspirium was positively correlated with forced expiratory volume in 1 s (%) (r = 0.636, p = 0.001) and forced vital capacity (%) (r = 0.646, p = 0.001) values. No significant correlation was found between diaphragm thickening fraction and forced expiratory volume in 1 s or forced vital capacity.
Conclusion: Ultrasound can provide valuable information about diaphragm morphology and quantify diaphragm contraction.
Keywords: Cobb angle; Musculoskeletal ultrasound; Pulmonary function.